OK, all the underclassmen who want to enter the NFL Draft have made their decisions.

The players and draft experts know - or at least think they know - where each of the underclassmen will go in the draft. But what about the team they are leaving behind? What happens to the ol' alma mater?

Here's our look at the impact the college teams will feel. In addition, we look at who will take over for the guys who are leaving.

While the NFL hasn't officially released the list of underclassmen who have declared, this list is made up of the players who have made public announcements.

NOTE: The "impact" section is ranked from five stars (meaning they player will be extremely difficult to replace) to one star (meaning the player will be easy to replace).

Arkansas

WHO: TBs Felix Jones and Darren McFadden: McFadden was expected; Jones was a bit of a surprise. So, who's left to carry the ball? Brandon Barnett, a junior college transfer who saw some time this season, and Michael Smith - who is too small (5-7 and 170 pounds) to be an every-down back - should get the bulk of the carries in spring ball. De'Anthony Curtis, considered the best prep player in Arkansas, has committed to the Hogs. If he follows through and signs, he'll be in the mix in the fall. THE IMPACT:BUZZ: Losing McFadden is bad enough. Losing Jones exacerbates the problem. The one good thing is new coach Bobby Petrino relies less on the run than departed coach Houston Nutt.

Auburn

WHO: DT Pat Sims: Sims' departure means the Tigers will be looking for two new starting defensive tackles. DE Sen'Derrick Marks, who is 6 feet 1, played some tackle this season and could move inside. Zach Clayton almost certainly will head into spring ball as a starting tackle. Also in the mix will be Mike Blanc, Jemarcus Ricks, Kyle Coulahan and perhaps a freshman or two.THE IMPACT:BUZZ: Sims was coming into his own and would have been one of the best defensive tackles in the SEC in 2008.

Boise State

WHO: OT Ryan Clady: The Broncos will have two new starting tackles - and four new starting linemen - next season. Nate Potter and Matt Slater look as if they will get first shot at the tackle spots.THE IMPACT:BUZZ: It's not surprising, but it still leaves a huge void. In essence, Boise will have a rebuilt offensive line – and that line will be protecting a new starting quarterback.

WHO: CB Orlando Scandrick: His decision was a surprise. Brandyn Thompson looks as if he will get first shot at the job. With Scandrick's decision, Boise will have two new starters in the secondary next season.THE IMPACT:BUZZ: The shock value alone hurts. But Boise looks as if it can weather Scandrick's departure better than Clady's.

California

WHO: WR DeSean Jackson: Jackson had a down junior season - for him, at least - but his speed and big-play ability excite NFL scouts. His departure means the Golden Bears will lose their top three wide receivers and their top five receivers overall. LaReylle Cunningham is the only wide receiver on the roster who has caught a pass, and he has eight receptions in his career. Big things are expected from Michael Calvin, who redshirted as a freshman this season. Jeremy Ross, a redshirt freshman who didn't catch a pass this season, is another who needs to produce. Cal also has commitments from two standout receivers, and the opportunity for ample playing time will be there.THE IMPACT:BUZZ: While it was no surprise, it certainly leaves the receiving cupboard bare for the Golden Bears. Cal will have a new starting tailback, a new tight end, two new starting receivers and - possibly - a new starting quarterback. A lot of young guys will need to produce immediately.

Clemson

WHO: DE Phillip Merling: Merling probably could've used another season, but chose to leave anyway. Incoming freshman DaQuan Bowers already is enrolled and will go through spring practice. Kevin Alexander - a high school teammate with Spiller in Lake Butler, Fla. - looks to be the other guy in the hunt. Kourtnei Brown has an outside shot.THE IMPACT:BUZZ: Merling would've been one of the best defensive players in the ACC this fall and one of the 10 best defensive ends in the nation. His departure means Bowers must produce as a freshman.

Florida

WHO: DE Derrick Harvey: Florida's pass rush took a hit with this announcement. Jermaine Cunningham and Carlos Dunlap are the early leaders to be the starters at end next season.THE IMPACT:BUZZ: It's not a surprise, but it hurts. The Gators struggled to get a pass rush with Harvey, one reason its young cornerbacks had so much trouble. The Gators have a lot of young talent at defensive end, but it's unproven.

Florida State

WHO: DT Letroy Guion: His surprising departure means FSU's line depth takes a hit. Guion started eight games and was FSU's leading tackler among interior lineman. Budd Thacker, Paul Griffin and Kendrick Stewart look as if they will be the main guys in the mix for the two starting tackle spots, with Justin Mincey also a possibility.THE IMPACT:BUZZ: FSU's defense wasn't up to its usual standards this season, and Guion would've been a force in the middle. His departure means some guys who haven't played with that much consistency need to do so.

WHO: LB Geno Hayes: Hayes was the Seminoles' second-leading tackler, and Marcus Ball likely gets first crack at replacing him. Touted freshman Nigel Bradham has enrolled early. Even with Hayes' departure, linebacker should be FSU's strongest position in the fall.THE IMPACT:BUZZ: If the Seminoles could afford to lose a player, it was at linebacker. Hayes played well, for the most part, and his speed will be missed. But unless a rash of injuries hits at linebacker, FSU will be fine.

WHO: QB Xavier Lee: Lee was a mega-hyped prospect out of high school but never came close to living up to his billing. His departure means Christian Ponder has a clear-cut path to be the No. 2 guy behind starter Drew Weatherford.THE IMPACT:BUZZ: It might actually be a good thing Lee is gone. The reason? No more quarterback controversy - well, unless Ponder tears it up in practice and Weatherford struggles.

Hawaii

WHO: WRs Davone Bess and Ryan Grice-Mullins: We're grouping these guys together to make a point. Hawaii is losing its coach, its quarterback and its top four receivers (two, C.J. Hawthorne and Jason Rivers, were seniors; the others are Bess and Grice-Mullins). Assuming the Warriors run the same pass-happy offense - or at least a variation of it - look for Malcolm Lane, Greg Salas, Aaron Bain and Michael Washington to be the leading candidates at receiver in spring ball. Some incoming junior college transfers also likely will get a chance.THE IMPACT:BUZZ: The Warriors' offense has been gutted of its playmakers.

Illinois

WHO: TB Rashard Mendenhall: Mendenhall was the Big Ten offensive player of the year, and his departure leaves a void. Daniel Dufrene was the No. 2 tailback this season, but Troy Pollard and Walter Mendenhall, Rashard's older brother, also will get an opportunity to be the starter. Freshman Mikel LeShoure has enrolled early and will go through spring ball, and the Illini figure to sign at least one more high school tailback as well.THE IMPACT:BUZZ: It hurts when you lose a league player of the year early. His production will be hard to replace. It's not a surprise he left, but it still leaves a big hole to fill. This puts more pressure on QB Juice Williams to be a more effective passer.

Indiana

WHO: WR James Hardy: His decision isn't surprising, but it does hurt - big-time. He caught 16 of the Hoosiers' 28 TD passes, and there doesn't appear to be anyone on the roster who can step up and be a legit go-to guy. Instead, it looks as if IU will use a spread-the-wealth formula. Still, the Hoosiers need someone to emerge from the group of Ray Fisher, Andrew Means (if he doesn't sign to play pro baseball), James Bailey, Brandon Walker-Roby, Chris Banks and Terrance Turner (if he has recovered from a severe knee injury). IU also has commitments from four nice-sized receivers, so you can expect at least one freshman to see time early.THE IMPACT:BUZZ: Hardy scared every defensive back who lined up opposite him. No other receiver on the roster does that.

Kansas

WHO: OT Anthony Collins: Collins' departure means the Jayhawks will have two new starting tackles. It looks as if Matt Darton, Jeff Spikes and junior college transfer Nathan D'Cunha - an Australian who already has enrolled - will be the three main competitors. Ian Wolfe also should get a shot.THE IMPACT:BUZZ: Collins had an excellent season and would've been one of the nation's top-five offensive tackles next season. And, man, when you have top-notch left tackles, it hurts when they leave. KU looks to have some talent at tackle, but it is untested.

WHO: CB Aqib Talib: Talib's big-play ability will be missed, but the Jayhawks look to have two solid corners who can start next season in Chris Harris and Kendrick Harper. Harris was the Big 12's defensive newcomer of the year, but he became a starter only after Harper - a junior college transfer - was injured. Isiah Barfield and Anthony Webb also will get their opportunities in spring practice.THE IMPACT:BUZZ: No question Talib was a playmaker, but the Jayhawks actually look as if they will be fine at corner in 2008, assuming Barfield and/or Webb comes through to provide some depth.

Louisville

WHO: LB Lamar Myles: He was a productive college linebacker, but he lacks size and bulk. He may find that at 6 feet 1 and 220 pounds, numerous NFL teams will bypass him. Regardless, he leaves a hole to fill for the Cardinals, who have to replace all three starting linebackers.James Bryant, a transfer from Miami, looks to be the leading candidate to take over Myles' spot in the middle. Louisville likely will bring in at least three linebackers in this recruiting class.THE IMPACT:BUZZ: Replacing all three starting linebackers is tough. And while Myles was undersized, he always was around the ball and had twice as many tackles as any other Cardinal.

WHO: WR Mario Urrutia: He didn't play well in 2007 and was in coach Steve Kragthorpe's doghouse. Scott Long and Trent Guy likely will be the Cardinals' starting receivers this fall.THE IMPACT:BUZZ: Urrutia has talent, but he seemed to have issues with the new coaching staff. It may be better that he is gone. Spring practice is going to be huge for the Cardinals as they to develop some depth at wide receiver.

Maryland

WHO: LB Erin Henderson: Henderson, who recently graduated, leaves a big hole. Adrian Moten and Alex Wujciak, who missed this season with a knee injury, look like the likely candidates for the open job.THE IMPACT:BUZZ: His decision wasn't that big a surprise. While the Terps have enough bodies at linebacker, his production is going to be impossible to replace.

Miami

WHO: DE Calais Campbell: Campbell was better as a sophomore than as a junior, but he's still leaving. Eric Moncur returns as one starting end, and Courtney Harris will go into spring ball as the starter on the other side.THE IMPACT:BUZZ: Campbell would've been a preseason All-America despite a so-so junior season. UM must find some depth at end to help lessen the blow of Campbell's departure.

WHO: FS/SS Kenny Phillips: Phillips didn't play as consistently as expected, but he'll be a first-round pick like so many former UM defensive backs. Anthony Reddick, who missed this season with an injury, should move into Phillips' vacated starting spot. The other safety should be Lovon Ponder, who played only six games because of injuries this season.THE IMPACT:BUZZ: Phillips would've been the best safety in the nation in 2008. Ponder and Reddick have talent but also injury concerns. And depth now is an issue.

Michigan

WHO: WRs Adrian Arrington and Mario Manningham: The spread-option offense finds a way to get talented wide receivers the football, but Michigan will be looking to replace both its starting receivers. Greg Matthews almost certainly will be one; the other spot is wide open, and freshmen will get a chance to play immediately.THE IMPACT:BUZZ: Manningham's departure isn't a surprise. Given Arrington's performance in the Capital One Bowl and the coaching change, his departure shouldn't have been, either. Still, Michigan now has lost its tailback, its top two quarterbacks, its two best linemen and its two best receivers. That's an overhand right to the face, a left to the ribs, a jab to the chin, another body blow, then a solid right to the jaw. In other words, it hurts - a lot.

Michigan State

WHO: WR Devin Thomas: Thomas went from six catches in 2006 to a school-record 79 this season, and decided to try the NFL off his superb season. Deon Curry and Mark Dell would seem to be the likely candidates to start at wide receiver next season, but coaches are high on B.J. Cunningham. In addition, in a potential development that would strike fear into announcers everywhere, the Spartans could have two guys named Chris Rucker playing wide receiver next season: Chris D. Rucker and Chris L. Rucker, who could be moved from cornerback in the spring.THE IMPACT:BUZZ: There really was no other Spartans wide receiver opposing defenses had to worry about this season. Spring ball will be vital for finding depth at wide receiver.

Middle Tennessee State

WHO: OT Franklin Dunbar: Dunbar had started 30 consecutive games. Mark Thompson, who started at center this season but has played tackle before, looks like the best possibility to take over for Dunbar.THE IMPACT:BUZZ: Dunbar's decision means the Blue Raiders lose their best two linemen. Thompson's potential is good, but that also means you'll be breaking in a new center this fall.

North Carolina State

WHO: FS Dajuan Morgan: Morgan quietly put together an excellent season (he led the Wolfpack with 97 tackles and 13 pass breakups) and leaves a massive void. The Wolfpack simply are depth-shy at safety. J.C. Neal almost certainly will head into spring ball as a starter at one of the spots, but the other spot is up in the air. Javon Walker is recovering from a knee injury and likely won't be ready for spring practice. Jimmaul Simmons, who redshirted this season, and Robbie Leonard, a former walk-on, look to be contenders for jobs. Dominique Ellis - who signed last year but didn't enroll until this month - is another possibility, although corner might be his best position. It seems a certainty that at least two true freshmen will play at safety in '08.THE IMPACT:BUZZ: Morgan didn't get much national notice, but he had a big-time season for coach Tom O'Brien. His loss is huge for the Wolfpack, not only because of his production but also because of the Wolfpack's lack of depth at the position.

Ohio State

WHO: DE Vernon Gholston: He was the only one of four key Buckeyes underclassmen to leave early, but he'll also be the easiest to replace. Lawrence Wilson, Robert Rose and Cameron Heyward give the Buckeyes star-quality ends, though they need to develop depth beyond that trio.THE IMPACT:BUZZ: Yes, Gholston was Ohio State's sack leader, with 14. But the Buckeyes should be fine up front in '08 assuming the young guys at end step up to provide depth.

Oklahoma

WHO: WR Malcolm Kelly: Kelly was superb in the first half of the season but faded in the second half. Still, he was a playmaker on the outside. The Sooners have talent waiting to take over for him. Quentin Chaney, who had a nice game in the Fiesta Bowl, likely gets first dibs at the job. Tyler Stradford, Adron Tennell and Ryan Broyles also will get their chances. Tennell, though, is recovering from a knee injury and will miss spring practice. OU will bring in some freshman receivers who will have ample opportunity to play immediatelyTHE IMPACT:BUZZ: Of all the OU underclassmen going pro, Kelly will be the easiest to replace. Chaney is a senior with all the physical tools, and perhaps the Fiesta Bowl performance shows that he finally has put everything together. Keep an eye on Stradford, who may be the fastest Sooners player.

WHO: LB Curtis Lofton: Lofton was the Big 12 defensive player of the year and depth behind him was questionable, meaning he's going to be tough to replace. OLB Ryan Reynolds could move inside. But Reynolds has had knee problems and also struggles in passing situations. Mike Reed, a touted junior college transfer who didn't do much this season, is another possibility.THE IMPACT:BUZZ: If Reynolds does move inside, which seems likely, OU will have new players starting at each of the three linebacker positions. This is Oklahoma, though, and there's talent waiting in the wings; it's just untested talent.

WHO: CB Reggie Smith: Smith's decision means OU will have to replace both starting cornerbacks. Dominique Franks started for Smith in the Fiesta Bowl because of Smith's toe injury and seems likely to get a chance to earn the starting spot permanently. Brian Jackson, Desmond Jackson and Jamell Fleming also should be in the hunt. It's also possible that Lendy Holmes, who moved to safety from cornerback this season, could move back to corner. Holmes has some academic issues, though.THE IMPACT:BUZZ: Losing an all-conference corner always hurts. The Sooners have some talent at corner, but it's young and unproven.

Oklahoma State

WHO: QB Bobby Reid: Reid lost his starting job to Zac Robinson early in the season and wasn't going to get it back. THE IMPACT:BUZZ: Reid was a mega-recruit who never quite lived up to the hype. His legacy at Oklahoma State will be the memorable Mike Gundy rant defending him without referring to him by name.

Oregon

WHO: TB Jonathan Stewart: Stewart had a big season, but the Ducks have some talent ready to replace him. Whether that talent is healthy is another concern. Jeremiah Johnson was the No. 2 tailback for much of the season until suffering a knee injury; Johnson has the talent to be a feature back in the Pac-10 - assuming he's healthy. Andre Crenshaw showed some ability after Johnson was hurt. Junior college transfer LaGarrette Blount is a big back (6 feet 2, 235 pounds) who already has enrolled. THE IMPACT:BUZZ: Stewart was one of the nation's best backs, and it's hard to imagine one guy adequately replacing him. Given that Oregon also lost QB Dennis Dixon, to say the Ducks' backfield is a concern is an understatement. Still, the Ducks look to have the pieces in place to have a nice tailback-by-committee.

Penn State

WHO: CB Justin King: King has a ton of talent, but it doesn't always show. And he's going to have to become stronger and more physical. He already has his degree, and his speed will excite some teams. Penn State's starting corners in 2008 should be Lydell Sergeant andA.J. Wallace, but depth is a huge concern. THE IMPACT:BUZZ: King was shaky at times this season, and looked outright overmatched at times, too. Still, four-year starters at corner are a good thing to have. Finding some backup corners who can play will be a high priority in spring practice.

Rutgers

WHO: TB Ray Rice: Rice did yeoman work for the Scarlet Knights the past three seasons and decided it was time to go. Kordell Young is coming off a severe knee injury and won't be 100 percent during spring ball. That gives Mason Robinson and Jourdan Brooks time to impress the coaches. Brooks is a big back with speed, and he could emerge as the starter. THE IMPACT:BUZZ: Rice was such a huge part of Rutgers' offense, and it's hard to imagine one back being as productive as he has been. But there is some talent on hand. Also worth noting is that Rutgers lost three starting offensive linemen, meaning the new guy will be running behind a rebuilt line.

Syracuse

WHO: WR Taj Smith: Smith was the Orange's No. 2 receiver this season, but he's 24 and felt it was time to go pro. Lavar Lobdell and Da'Mon Merkerson are holdovers who will get a chance to take Smith's starting spot. The Orange also has a commitment from Marcus Sales, a touted freshman who will get every opportunity to play immediately. THE IMPACT:BUZZ: Smith's departure means the Orange won't have a nice 1-2 punch at receiver with Mike Williams. Given Syracuse's offensive problems, losing somebody who can make plays isn't good.

Tennessee

WHO: LB Jerod Mayo: Mayo - and the rest of the Vols' defense - struggled early this season, but Mayo was playing at a high level by the time the season ended. He graduated in December, so his departure wasn't really that big a surprise. However, it does mean the Vols will have two new starting linebackers in '08. Ellix Wilson should get first crack at Mayo's old spot. THE IMPACT:BUZZ: It can be tough to replace good linebackers, so the Vols have some work to do in spring ball finding guys to take over for Mayo and senior Ryan Karl. Wilson and Rico McCoy look like for-sure starters. The other spot is the problem.

Texas

WHO: TB Jamaal Charles: Vondrell McGee looks like he'll be the guy to replace Charles, but there is no shortage of candidates. Texas also has commitments from five potential tailbacks. THE IMPACT:BUZZ: Texas should never have problems at tailback.

WHO: TE Jermichael Finley: His decision was a head-scratcher. He might have been the fifth- or even sixth-best tight end in the Big 12 this season. While he has proven he can get down the field and be a deep threat, consistency was lacking. The new starter in the spring likely will be Blaine Irby, who played this season as a true freshman. Peter Ullman, Josh Marshall, Ian Harris and Ahmard Howard will vie for the No. 2 job.THE IMPACT:BUZZ: Texas has a ton of talented guys trying for the job. The Longhorns will be fine at tight end.

Texas A&M

WHO: TE Martellus Bennett: Though Bennett was underutilized and didn't put up the numbers he could have, his departure isn't a surprise. But it leaves a hole, as he and senior Joey Thomas were the only tight ends on the roster to catch a pass. Frank Avery, who redshirted this season as a freshman, likely gets first crack at the job. THE IMPACT:BUZZ: The Aggies' tight end job is wide open, though Avery was a touted recruit in the 2007 signing class.

UCF

WHO: TB Kevin Smith: Smith's decision creates a massive hole in UCF's offense. Phillip Smith - no relation - will head into spring ball as the new tailback, but depth is a concern. A true freshman could end up being the No. 2 guy. THE IMPACT:BUZZ: Smith was the nation's leading rusher this season and his season total was the second-highest in Division I-A history. That kind of production is impossible to replace. And tailback depth now is a huge problem.

USC

WHO: G Chilo Rachal: Rachal could have used another season in college, but a family matter evidently led him to leave now. His departure means USC will have four new starting offensive linemen next season. That sounds bad, but because of injuries this season, the Trojans had 10 players start at least one game on the line. Still, Rachal's replacement looks as if he will be the line's weak link. Going into spring ball, the likely starters at guard are Jeff Byers - the only returning starter on the line - and Zack Heberer. Martin Coleman and Alex Parsons also should be in the mix, as will touted freshman Matt Meyer - who already has enrolled and will get an opportunity in the spring. THE IMPACT:BUZZ: This is a rare instance where injuries helped a bit in the long run, as Heberer started two games when Rachal was hurt. The Trojans also will have the nation's best incoming line class.

Vanderbilt

WHO: WR Earl Bennett: Bennett leaves as the SEC's career leader in receptions, so his departure creates a huge hole. Alex Washington should get the first crack at taking Bennett's spot in the lineup. THE IMPACT:BUZZ: Bennett had a legit chance to become Division I-A's career receptions leader, and Vandy isn't going to be able to adequately replace him.

Virginia

WHO: G Branden Albert: His decision to turn pro means the Cavs will have two new starting guards next season. Going into spring ball, it looks as if Patrick Slebonick and B.J. Cabbell will get first dibs. THE IMPACT:BUZZ: Albert was underrated nationally and truly could have been dominant in '08. And having two new starting guards - as well as a new starting center - won't make the Cavaliers' tailbacks too happy.

Virginia Tech

WHO: CB Brandon Flowers: Flowers' decision is a blow, but it would've been even worse had Victor Harris also decided to leave. Rashad Carmichael, Stephan Virgil and Cris Hill look to be the guys who will be in the hunt to replace Flowers. THE IMPACT:BUZZ: Flowers and Harris would've been the nation's best cornerback duo. Had Harris also left, the impact would have been staggering. But Harris' return softens the blow somewhat, and the Hokies should be fine.

West Virginia

WHO: WR Darius Reynaud: Reynaud had 64 catches and 12 TDs; the other wide receivers on the roster combined for 67 receptions and two scores. Tito Gonzales and Wes Lyons, who is 6 feet 8, will get first crack at replacing Reynaud as the starter. Returning starter Dorrell Jalloh could emerge as the go-to receiver. THE IMPACT:BUZZ: Reynaud was the only wide receiver of note for WVU this season. Because of his height, Lyons is an intriguing talent. Still, it's hard to see anyone currently on the roster making the same impact as Reynaud.

WHO: TB Steve Slaton: Slaton's departure means more carries - a lot more - for Noel Devine. It also means the No. 2 job now is wide open. There is no clear-cut leader for that job. One thing to watch for with Devine is whether he can be an effective receiver out of the backfield.THE IMPACT:BUZZ: Devine is a special talent, assuming he can continue on the straight-and-narrow. At the same time, think of what WVU could've done with Devine and Slaton - not to mention Pat White - in the same backfield in '08. If WVU can come up with a solid No. 2 tailback, they won't miss Slaton that much. If they don't, they could be in trouble.

Wisconsin

WHO: CB Jack Ikegwuonu: His departure could create a problem for the Badgers. The likely starters at corner would seem to be Allen Langford and Aaron Henry. One problem: Both are coming off severe knee injuries. Look for Josh Nettles, Niles Brinkley and Otis Merrill to try to make their cases during spring ball. Starting FS Shane Carter also has some experience at corner. THE IMPACT:BUZZ: Ikegwuonu would've have gone into the '08 season as one of the nation's best corners. That the projected starting corners are coming off knee injuries has to be a bit worrisome to the Badgers.